By Jonathan Stempel June 2 (Reuters) - An anonymous bidder has agreed to pay $3,300,100 at auction to have a private lunch with Warren Buffett, the billionaire chairman of Berkshire Hathaway Inc . The winning bid came near the end of a five-day online auction on eBay to benefit the Glide Foundation, a San Francisco charity that serves people who are poor, homeless or battling substance abuse. It was the third highest price in the 19 years Buffett has offered lunc